When planning a road, or railroad line, a model is created which shows the final alignment contouring of terrain along the road. The final contouring includes earthworks and structures built in the course of constructing the road. An important part of the contouring includes a cut/fill plan which details portions of the road which are cut and then used to fill other portions of the road. For example, a portion of a hillside may be cut and used to fill in a ravine or gully. Typically, this results in a more level roadbed and reduced construction costs.
After planning which portions of the terrain are to be cut and filled. A mass haul diagram is created which details the mass, direction, and average length of haul of material from the cut site to the fill site. Typically, the mass haul diagram shows movement of material from the center mass of where the fill material is taken from the cut site to center mass of the fill site where the fill material is deposited.